1. Field of the Invention
The invention relates to a compound connecting rod, sleeve and offset crankshaft assembly that causes the top dead center of the piston crown to occur after the top dead center of the crankshaft rod journal during the compression and exhaust strokes of the piston.
2. Description of the Relevant Art.
Numerous types of compound pistons, i.e., pistons having a plurality of linked movable elements within each cylinder of the engine block, have been developed for internal combustion engines. In some of these prior art configurations, the top of the piston, i.e., the crown or head of the piston, is only partially extended at the upper end of the crankshaft stroke. The maximum amount of compression, i.e., the maximum extension of the telescoping members, occurs when the crank throw is past dead center. The complication of most of these expanding piston/rod/cranksaaft assemblies is sufficient to burden their production with excessive production and maintenance costs. In some of the prior art, the two halves of an expanding piston telescope as the piston moves up and then again as the piston moves down. Other expanding pistons reach top dead center at the same time as the crankshaft throw reaches top dead center and the piston crown also reaches its maximum distance from the crankshaft throw when the crankshaft throw is at the top and bottom dead center positions. Among the prior art relative to expanding pistons and other devices having linkage systems which relatively move the pistons, as the connecting rod moves up and down, may be mentioned U.S. Pat. Nos. 1,379,115; 1,420,236; 1,430,491; 1,671,708; 2,368,412; 2,458,111; 3,034,362; 3,859,976; 3,908,623 and 4,203,406.